1. Field of the Invention
The invention relates generally to axial flow combines and more particularly to an improved rotor drive anti-trash system.
2. Prior Art
FIG. 4 of this application shows an example of the prior art in protecting a rotor drive shaft against wrapping of crop material about the shaft and minimizing accumulation of "trash" adjacent the drive system of the rotor. The rotor 10 is shown in fragmentary section and includes a cylindrical drum 12, a rear end wall 14, and a central drive shaft 16 defining the axis of rotation of the rotor. The rotor drive shaft 16 is driven through a gear case 18 having an input shaft 20.
It will be noted that the rotor drum 12 extends rearwardly beyond the rotor end wall 14 so as to axially overlap a ring 22 fixedly secured around the gear case 18. It is this overlap which inhibits the entry of crop material into the generally annular space about the drive shaft 16 and between the end wall 14 and gear case 18. In practice the threshing process creates small particles of crop material which can pass between the drum 12 and ring 22 and collect in the above described annular space. The accumulation of material is particularly undesirable when it is very dry and thus subject to combustion by the heat of friction of the rotating mechanism.
While it might appear that an obvious solution lies in developing a more effective seal between the rotor and gear case, the problems of wear, repair, and replacement of such a seal remain for solution.